router.get('/$1',async (req,res,next)=>{
    
    let {$2} = req.query
  
    let data = {}//最终要返回的数据格式  msg,status,result
    //1. 写sql
    let sql = ` `
    //2. 执行sql
    let {result} = await MyQuery(sql) //{ err,result }

    //3. 要处理成规范、格式化的json数据
    data = {
        msg:'OK',
        status:200,
        result
    }
    res.send( data )
})